document.write( "Question 1161014: You owe your parents $27,000 (in present day dollars) and want to repay them in equal amounts the first to occur in 3 years from today and the other in 8 years from today. If the interest rate is 6.1% per annum compounding monthly, what will be the amount of each repayment? \n" ); document.write( "
Algebra.Com's Answer #784558 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
to make this easier for you to see, i've assigned letters to the numbers.
\n" ); document.write( "you can then replace the letters with numbers to determine for yourself that the answer is the answer i gave you.\r
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\n" ); document.write( "\n" ); document.write( "let a = (1 + .061/12) ^ 36
\n" ); document.write( "let b = (1 + .061/12) ^ 96
\n" ); document.write( "let x = the amount you are looking for.\r
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\n" ); document.write( "\n" ); document.write( "x/a is the present value of the payment in the 48th month (4th year).
\n" ); document.write( "x/b is the present value of the payment in the 96th month (8th year).\r
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\n" ); document.write( "\n" ); document.write( "your formula is x/a + x/b = 27000.
\n" ); document.write( "multiply both sides of this formula by a*b to get:
\n" ); document.write( "a*b*x/a + a*b*x/b = a*b*27000
\n" ); document.write( "simplify to get:
\n" ); document.write( "b*x + a*x = a**b*27000
\n" ); document.write( "factor out the x on the left side of the equation to get:
\n" ); document.write( "x*(a+b) = a*b*27000
\n" ); document.write( "divide both sides of the equation by (a+b) to get:
\n" ); document.write( "x = a*b*27000/(a+b)\r
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\n" ); document.write( "\n" ); document.write( "your answer will be 18649.41705 \r
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\n" ); document.write( "\n" ); document.write( "that's the payment in the 48th month and the 96th month that will satisfy the 27000 loan.\r
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\n" ); document.write( "\n" ); document.write( "the present value of that for 36 months = 18649.41705 / (1 + .061/12) ^ 36 = 15537.84162.
\n" ); document.write( "the present value of that for 96 months = 18649.41705 / (1 + .061/12) ^ 96 = 11462.15838.
\n" ); document.write( "their sum = 27000 which is the present value of the loan.\r
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